The overall purpose of this study is to evaluate the effectiveness of an Internet web-based intervention on smoking cessation among college students. A randomized treatment and control group pretest-posttest design is employed in study. The specific aims of the proposed study are to: (1) assess the differences in the mean number of cigarettes smoked, mean quit rate, and mean number of quit attempts between the intervention and control groups; (2) to investigate changes in stage of readiness to quit based on the Transtheoretical Model of Change between the intervention and control groups; and (3) to conduct a process evaluation of the intervention. The University of Georgia campus will serve as the site for the study. Participants will be college students 18 years and older, smokers, and able to access the Internet. They will be recruited in introductory classes on campus, major campus facilities, and at the university health center. Seven hundred and eighty- eight undergraduate smokers will complete an online, baseline assessment and will be randomly assigned to one of two conditions: Condition 1 (Transtheoretical Model Treatment) consists of four web- based, stages of change tailored sessions aimed at reducing cigarette smoking and promoting smoking cessation with social support components; and Condition 2 (CONTROL) consists of visiting a generic college health website. Follow-up assessments will be completed at one week and 6-months following the last intervention session. The total time to recruit participants and conduct the intervention is expected to be 24 months (following a 3-month startup and pilot period). Each participant will be followed for 6 months. We estimate that we will need 394 students per condition for a total of 788 students. To test the hypotheses, ANOVAs and chi-square analyses will be used to test the differences among group means and proportions. To conduct the process evaluation, we will analyze open-ended questions by coding responses into categories to draw themes related to satisfaction and usefulness of the intervention format.